Thank you for bringing this one back.
Since posting, through DNA, I have discovered that my grandfather was William Rothwell Wolfenden who was born in Oldham in 1884 and died in 1937 in Manchester. He was married at the time of his relationship with my grandmother and had five children with his wife, one of them being born the same year as my mother! I have found him on the 1921 census so do know a little bit more about him.
I would love to see a picture of him but have had no success so far.
Thank you for your interest.